historyman historyman
  • 01-03-2017
  • Mathematics
contestada

If a + 3b = 13 and a + b = 5, the value of b is?

A. 1
B. 4.5
C. 7
D. 4

Respuesta :

AnimeBrainly
AnimeBrainly AnimeBrainly
  • 01-03-2017
the value of b is 4

a=1

1+3(4)=13
1+4=5

Answer Link
awsomejaguar
awsomejaguar awsomejaguar
  • 01-03-2017
Ans: D
First, multiply a+b=5 by 3 to make it 3a+3b=15
Second, subtract this equation from a+3b=13 to give 2a=2
Therefore, a=1
Substitute this into a+3b=13, to give 1+3b=13
So, 3b=12
Divide this 3b=12 by 3 to get for.
Therefore, b=4
Answer Link

Otras preguntas

There are four levels of economic development; what are they?
3/8 plus 1/2 Fractions
4. Which is an algebraic expression for the word phrase "8 less than the product of 12 and a number x?
subtract x^2-6x+4 from 2x^2+4x-8 ( )-( ) step 1: step 2: step 3:
Please answer soon (40 Points)
Moses is important in the history of the Israelites because
Scientific research shows that our global climate is changing. The global sea level is rising and ocean temperatures are increasing. Which of the following best
Which of the following best describes the purpose of the ideal study environment? A)To make you more physically comfortable and alert when studying B)To help yo
What are the Kelvin and Celsius temperature scales based on?.
another testing only just to find this account